[tlbuild] Building on the Macintosh

[Richard Koch]

Folks,

Returning from a trip, I tried the latest sources. Here are my experiments

1) On High Sierra, latest mac OS, everything builds and passes all tests, producing 429 exeutables

2) On El Capitan, the actual mac OS we want to use for building in 2018, icu builds fine, but then an error occurs when XeTeX tries to read the umachine.h file it creates because XeTeX does not understand char16_t.

As I understand it, char16_t used to be defined as "large enough to hold a 16 bit character, but was later added as one of the basic types in C++ with exactly the size needed for a 16 bit character. Since icu does bit-copy operations, it needs that "exactly the same" condition.

3) Next I tried building on El Capitan with the flag

	--disable-xetex

Then everything built and passed all tested, and I got 421 executables.



Therefore the good news is that this problem only occurs in XeTeX. My conjecture is that C++ is fine on El Capitan, but XeTeX is using ordinary C and confused by char16_t. 

At this point I took a suggestion from Apostolos Syropoulos and tried to modify it. My change to the command starting the build was

	CONFIG_SHELL=/bin/bash CC="clang -Dchar16_t=uint16_t" .Build --enable-xindy CLISP=/Users/koch/clisp/clisp-build/clisp

This sadly failed in the same XeTeX spot as before. 


I suspect it is because I don't understand the correct flag to use. Suggestions?

Dick Koch